Apparatus for remote control of drifter rotation



July 16, 1968 C. .1. scHoRx-:R

APPARATUS FOR REMOTE CONTROL OF DRIFTER ROTATION.

- Filed Jan. l2, 1966 FIG. 5

OTTO J'. SCHORER I N VEN TOR.

FIG.3.

United States Patent 3,392,957 Patented July 16, 1968 Office 3,392,957APPARATUS FOR REMOTE CONTROL GF DRIFTER ROTATIN Otto J. Scherer,Northampton, Mass., assignor to Worthington Corporation, Harrison, NJ.,a corporation of Delaware Filed Jan. 12, 1966, Ser. No. 520,263 4Claims. (Cl. 253--1) This device relates generally to an automaticcontroller for use with percussion tool apparatus, such as pneumatictype rock drills and their associated compressor equipment, and moreparticularly, to a remote safety control device for controlling thedirection of rotation of the drill steel in drilling equipment andautomatically preventing the operator of said equipment from reversingthe rotation of the drill steel in the drifter, when the drifter isbeing operated at full power.

In percussion tools, such as pneumatic type rock drills, there isprovided in the drifter a reversing mechanism. This reversing mechanismis utilized in uncoupling drill steel sections. These drill steelsections are the rotating components of the drilling equipment, and arecommonly -connected by threaded connections which form couplings betweensuch parts as the rie bar and riiie nut, the piston hammer and chucknut, the chuck drive ring and striking bar, etcetera. A sudden reversalof rotation may loosen any of these threaded connections, and couldresult in loss of steel sections or serious damage to the interior ofthe drilling equipment. It is desirable, therefore, to utilize onlylight hammer action and slow reverse rotation for changing drill steelsections.

In the prior art a common three-way valve located at the operatorsstation was usually employed to provide fluid pressure to actuate thereversing mechanism in the drifter. A valve of this type has not provento be entirely satisfactory, as it permits the operator to change thedirection of rotation from normal drilling position, i.e. forwardrotation, to reverse rotation, at full drifter power.

The present invention prevents the operator from reversing the rotationof the drifter at full drifter power. It operates automatically by wayof a cam-actuated valve interlock. This interlock is energized by thefluid in the power supply line to the percussion tool. It is so disposedthat the power supply line to the tool must be closed off, before thereversing mechanism can be shifted from either a forward or a neutralposition into a reverse position. The control mechanism is such thatonly the power supply line is shut down and not the power supply itself.Thus, pressure uid is still available to operate the reversingmechanism. When the power supply line is closed, the deviceautomatically disengages itself from the valve cam and allows theoperator to shift the reversing mechanism into reverse. The operator maythen select the proper reverse rotation speed for safety uncouplingdrill steel sections.

Accordingly, it is the. object of this invention to provide a means toprevent the operator from reversing the direction of rotation of thedrill steel in pneumatic type drilling equipment at full drifter power,by providing a remote drifter rotation control valve with interlockingsafety means.

It is another object of this invention to provide a remote safetycontrol `device for use in conjunction with percussion tool apparatus toprevent the operator of such apparatus from reversing the rotation ofthe rotating tool parts while the Itool is being supplied with fullpower, which device is automatic in both its interlocking anddisengaging functions.

These andother objects and advantages of the invention will becomeevident from the following description with reference to theaccompanying drawings of which:

FIGURE 1 is a general assembly drawing of percussion tool apparatus;

FIGURE 2 is a top view of the drifter backhead;

FIGURE 3 is a detail drawing in partial section of the remote rotationcontrol valve;

FIGURE 4 is a section View taken along the line 4--4 of FIGURE 3;

FIGURE 5 is a section view taken along the line 5--5 of FIGURE 3; and

FIGURE 6 is a top view of the remote rotation control valve.

Referring to the drawings, FIGURE 1 .shows a pneumatic hammer type rockdrill 1 connected by means of a power supply line 2 to a compressor. Thebasic elements of the drill are shown, such as, the drill bit 4, thedrill steel 5, the drill steel coupling 6, and the drifter 7. Thedrifter backhead 8 contains a built-in reversing mechanism. Thisreversing mechanism is connected to the remote rotation control valve 10by means of supply lines 11 and 12. The main power supply line 2contains a power regulating valve 13. The 4remote drifter rotationcontrol valve 10 is connected to the main power supply line 2 upstreamof the power control valve 13 by means of feeder 'line 14. Integral withthe remote drifter control valve is interlock 15, which itself isconnected to the main power supply line 2 downstream of the powercontrol valve 13 by means of feeder line 16.

The various connections just described are shown in m'ore detail inFIGURE 3, in which the remote drift rotation control valve is shown inpartial cross section. The valve consists of a valve body 17, a valveplug 18, a means for rotating the plug, eg. handle 19, and an interlockmeans 15.

The valve body contains a forward port 21 which is connected to thereversing mechanism in the drifter back- -head by means of line 11,FIGURES 1 and 2, and freverse port 22 which is connected to the oppositeside of the reversing mechanism -by means of line 12, FIG- URES 1 and 2.Below each of these ports there are vent ports in the valve body; whichvent ports are designed to be in fluid communication with theirrespective forward and reverse ports depending on the position of thevalve plug 18.

The valve plug is shown in the forward position in FIGURE 3. In `thisposition there is an open channel through which pressure fluid couldpass from the feeder line 14 into the valve inlet 25, and thence intothe valve plug chamber 26 from which it would pass through theconnecting port 27 in the valve plug, the forward port 21 in the valvebody, and line 11, thereby actuating the reversing mechanism so `that itwould be in its forward position. In this position the opposite side ofthe reversing mechanism is vented through line 12, and passages 22, 28and 24.

INTERLOCK MEANS Referring to FIGURE 4, the interlock 15, which isconnected at 9 to the main supply line, is shown in contact with thevalve plug 18 at point 29. As can be seen, the pin 30 does not lprotrudeinto the valve body cavity 31 which is occupied by the valve plug 18,which, as in FIGURE 3, is in its forward position. The pin 30 is anintegral part of the piston 32, which is slidably mounted in thecylinder 33 of the interlock mechanism 15.

FIGURE 5 is a section taken on the line 5-5 in FIG- URE 3. It shows thevarious passages in the valve plug 18. The passages designated 27 and 28are those depicted in FIGURE 3 and are the forward rotation passages.The passages designated 40 and 41 are the neutral position passages, andthe passages designated 42 and 43 are the reverse position passage.

OPERATION As the valve plug is rotated in a clockwise direction, thevarious passages will line up with the forward and reverse ports andtheir respective vents in the valve body. The various positions of thevalve plug 18 with respect to the valve body 17 control the reversingmechanism in the drifter backhead 8, by supplying control lluid toactuate the reversing mechanism as follows:

(a) In the forward position, as shown in FIGURES 3 and 5, the pressureiluid from the line 14 passes through the valve plug chamber 26 and outthe forward port 21, to the reversing mechanism in the drifter backhead8. When thus acted upon, the reversing mechanism 8 will cause clockwiserotation (i.e. forward rotation) of the drill steel 5, FIGURE l.

(b) In the neutral position, valve plug passages 4) and 41 will bealigned respectively with ports 21 and 22 in the valve body 17. Pressurefluid in the plug chamber 26 will ilow out of both ports simultaneouslyand equalize the pressure on either side of the reversing mechanism 8,thereby causing it to return to its neutral position wherein the drillsteel will not rotate.

(c) In the reverse position, passages 42 and 43 will be alignedrespectively with ports 21 and 22, and pressure fluid in chamber 26 willflow out of port 22, through line 12, and act upon reversing mechanism8, thereby causing it to move into its reverse position wherein thedrill steel will be caused to rotate in a counterclockwise direction.

Referring once again to FIGURE 4, note that the piston and cylinder arecontinuously acted upon by pressure fluid in the feeder line 16 whichemanates from the main power supply line 2, thereby maintaining the pin30 in constant contact with the valve plug 18. As can be seen, the valveplug at the point of contact 29 with the interlock means, has a camsurface 20. The pin 30, being acted upon by constant fluid pressurethrough the piston, acts as a cam follower when the plug is rotated.Thus, as the plug is rotated in a clockwise direction from the forwardposition as shown in FIGURES 3, 4, and 5, to the neutral position, aspreviously described in connection with FIGURE 5, the pin follows thecammed surface of the valve plug and is drawn into the valve body cavity31. With the pin thus engaged in the valve plug, it is impossible tocontinue to rotate the plug in a clockwise direction due to the stop 34.

The spring 3S exerts a force which is much less than the line pressureexerted by the fluid in the main supply line on the opposite side of thepiston. However, when the power control valve 13, FIGURE 1, is closed,the pressure fluid in the supply line is no longer communicating withthe feeder line 16, and can no longer exert a force against the piston32, and, therefore, the spring 35 will automatically eject the pin fromthe valve body cavity 31. This will enable the operator to continue torotate the valve plug in the clockwise direction from the neutralposition to the reverse position. The operator may now select the properreverse rotation speed for uncoupling drill steel sections by adjustingthe power control valve 13.

Referring to FIGURE 6, the handle 19 is shown keyed to the valve plug 18by means of key 38. Handle eXtension 39 is in engagement with stop 36 ofvalve body 17 with the valve in the forward position as previouslydescribed. When the handle is rotated a full 90 in the clockwisedirection, the valve plug is moved from a forward to a reverse position,at which point the handle extension 39 engages the stop 37 of the valvebody, thereby preventing further clockwise rotation. It is in thisposition that the operator selects the proper reverse rotation speed.

Forward rotation may be resumed when the operator rotates the handle ina counter-clockwise direction until it engages the stop 36.

It will be understood that various changes in the details, materials,and arrangements of parts which have been herein described andillustrated in order to explain the nature of the invention, may be madeby those skilled in the art Within the principle and scope of theinvention as expressed in the appended claims.

What is claimed is:

1. `In a rock drilling apparatus, the combination of:

(a) a percussion type drilling tool comprising, a rotating shaft, and arotational control mechanism for regulating the direction of rotation ofsaid shaft;

(b) a source of fluid under pressure;

(c) a pressure fluid supply line connecting said source of pressureiluid to said percussion tool;

(d) a regulating valve in said pressure fluid supply line for regulatingthe amount of pressure uid delivered to said percussion tool;

(e) remote valve means connected at its upstream side to the pressurefluid supply line upstream of said regulating valve and at itsdownstream side to the rotational control mechanism, to control the flowof fluid to said mechanism to operate said mechanism; and

(f) interlock means connected to the pressure fluid supply linedownstream of the regulating valve and disposed to coact With saidremote valve means to prevent said remote valve means from supplyingfluid to the rotational control mechanism for operating said mechanismso as to prevent said mechanism from reversing the direction of rotationof the shaft while fluid is continuously flowing through the regulatingvalve.

2. An apparatus asin claim 1 wherein:

(a) said remote valve means comprises,

(1) a multi-way valve having a valve body, and

(2) a valve plug rotatably mounted within said valve body to control theflow of fluid to operate the rotational control mechanism;

(b) said interlock means comprises,

(1) a body having a chamber therein,

(2) said chamber having an inlet at one end connected to the pressurefluid supply line downstream of said regulating valve and a port at theopposite end disposed within said valve body,

(3) a piston slidably mounted in said chamber intermediate said inletand said port and disposed to be acted upon by the pressure lluid insaid supply line to move said piston within said chamber toward saidport,

(4) said piston having a pin connected to it, said pin being slidablymounted in said port; and

(c) said pin being disposed to engage said valve plug to prevent saidvalve plug from rotating within said valve body thereby preventing saidplug from operating the rotational control mechanism in the drillingtool, whereby said mechanism is prevented from reversing the directionof rotation of the shaft while iluid is continuous-ly flowing throughthe regulating valve.

3. An apparatus as in claim 2 wherein a spring is mounted in the chamberof the interlock means between the port and the piston and is disposedto move the piston from the port toward the inlet of the chamber whensaid regulating valve is closed and the uid in the pressure fluid supplyline is no longer acting against the piston, thereby automaticallydisengaging the pin from the valve plug, whereby the plug may be rotatedto operate the rotational control mechanism and cause said mechanism toreverse the direction of rotation of the shaft upon opening of theregulating valve.

4. An apparatus as in claim 3 wherein:

(a) said valve plug has a cammed surface, and said pin is disposed toact as a follower on said cammed surface, said cammed surface having astop thereon for engaging said pin when pressure fluid is continuouslyflowing through the regulating valve and the valve plug is being rotatedin a clockwise direction;

(b) a handle connected to said valve plug to rotate said plug; and

(c) stops on said valve body to engage said handle to preventfurtherrotation when said plug is rotated in a clockwise direction froma forward to a reverse position or when said plug is rotated in acounterclockwise direction from a reverse to a forward position.

References Cited UNITED STATES PATENTS Gartin 91-45 Delano 253-1 Seborg253--1 Larcen 173-43 Wente 170-l35.74 Kurt et al 173-4 Tennis 137-624.27X

EVERETTE A. POWELL, J R., Primary Examiner.

1. IN A ROCK DRILLING APPARATUS, THE COMBINATION OF: (A) A PERCUSSIONTYPE DRILLING TOOL COMPRISING, A ROTATING SHAFT, AND A ROTATIONALCONTROL MECHANISM FOR REGULATING THE DIRECTION OF ROTATION OF SAIDSHAFT; (B) A SOURCE OF FLUID UNDER PRESSURE; (C) A PRESSURE FLUID SUPPLYLINE CONNECTING SAID SOURCE OF PRESSURE FLUID TO SAID PERCUSSION TOOL;(D) A REGULATING VALVE IN SAID PRESSURE FLUID SUPPLY LINE FOR REGULATINGTHE AMOUNT OF PRESSURE FLUID DELIVERED TO SAID PERCUSSION TOOL; (E)REMOTE VALVE MEANS CONNECTED AT ITS UPSTREAM SIDE TO THE PRESSURE FLUIDSUPPLY LINE UPSTREAM OF SAID REGULATING VALVE AND AT ITS DOWNSTREAM SIDETO THE ROTATIONAL CONTROL MECHANISM, TO CONTROL THE FLOW OF FLUID TOSAID MECHANISM TO OPERATE SAID MECHANISM; AND (F) INTERLOCK MEANSCONNECTED TO THE PRESSURE FLUID SUPPLY LINE DOWNSTREAM OF THE REGULATINGVALVE AND DISPOSED TO COACT WITH SAID REMOTE VALVE MEANS TO PREVENT SAIDREMOTE VALVE MEANS FROM SUPPLYING FLUID TO THE ROTATIONAL CONTROLMECHANISM FOR OPERATING SAID MECHANISM SO AS TO PREVENT SAID MECHANISMFROM REVERSING THE DIRECTION OF ROTATION OF THE SHAFT WHILE FLUID ISCONTINUOUSLY FLOWING THROUGH THE REGULATING VALVE.